Valve

ABSTRACT

A valve adapted for use with an internal combustion engine comprising a body having a passage therethrough and a valve element including a valve head and a valve stem. The valve element is mounted for movement on the body so that the valve head can open and close the passage. The valve stem projects through a bore in the body and has an insurance member mounted thereon which is engageable with an abutment to limit the maximum amount of opening of the valve. A peripheral wall substantially circumscribes the insurance member when the latter engages the abutment to prevent removal of the insurance member. The valve is biased toward a closed position by a spring which extends between the body and a valve spring retainer. The valve spring retainer is mounted on the valve stem by a split ring which is received in a counterbore in the valve spring retainer.

United States Patent [191 Anderson Oct. 2, 1973 1 VALVE [76] Inventor: Arthur S. Anderson, 25032 Armagosa Dr., Laguna Niguel, Calif. 92677 [22] Filed: June 18, 1971 1211 Appl. No.: 154,323

[52] US. CL. l23/90.67, 123/188 VA, 123/188 GC [51] Int. Cl. F011 3/10, F011 3/00 [58] Field of Search 123/90.67, 90, 188 VA, 123/188 GC [56] References Cited UNITED STATES PATENTS 3,217,699 11/1965 Dolza 123/188 2,171,668 9/1939 Oldham 251/337 2,753,857 7/1956 Smith 123/188 3,021,593 2/1962 Cousino 29/417 3,033,518 5/1962 Sampietro 251/337 7 FOREIGN PATENTS OR APPLICATIONS 486,144 9/1952 Canada 123/188 Primary Examiner-Laurence M. Goodridge Assistant ExaminerRonald B. Cox AttorneySmyth, Roston & Pavitt [57] ABSTRACT A valve adapted for use with an internal combustion engine comprising a body having a passage therethrough and a valve element including a valve head and a valve stem. The valve element is mounted for move ment on the body so that the valve head can open and close the passage. The valve stem projects through a bore in the body and has an insurance member mounted thereon which is engageable with an abutment to limit the maximum amount of opening of the valve. A peripheral wall substantially circumscribes the insurance member when the latter engages the abutment to prevent removal of the insurance member. The valve is biased toward a closed position by a spring which extends between the body and a'valve spring retainer. The valve spring retainer is mounted on the valve stem by a split ring which is received in a counterbore in the valve spring retainer.

1 Claim, 4 Drawing Figures PATENTEDUBI ems 3.7 62. 382

INUENW/f: Art/ w- S. Anderson Arroq/veys VALVE BACKGROUND OF THE INVENTION As is well known, valves for internal combustion engines are opened and closed in a predetermined sequence to control the movement of gases to and from the cylinders with the speed of movement of the valves being proportional to engine speed. Typically, valves of this type are biased by a spring toward the closed position and are opened by engine driven cams.

A problem with this construction occurs at high engine speeds in that the valves tend to float. Floating of a valve occurs when the energy of that valve is too great for its spring, in which event the cam and spring lose their control of that valve. When this occurs, the valve may travel too far into the cylinder and be struck or completely crushed or swallowed by the piston in that cylinder. In either event, severe engine damage occurs.

The spring which urges the valve closed normally acts between a portion of the engine and a valve spring retainer carried by the valve stem. Typically, a valve spring retainer is releasably mounted on the valve stem by removable wedges. When valve float occurs, relative movement between the retainer and the valve stem may occur which may cause cocking of the wedges and possible demounting of the retainer from the valve stem. In this event the valve would be swallowed.

SUMMARY OF THE INVENTION The present invention eliminates engine damage resulting from valve float by providing an insurance member on the valve stem which engages an abutment to limit the maximum amount of opening of the valve and hence the maximum distance which the valve can travel toward the piston. To facilitate assembly and disassembly, the insurance member can advantageously take the form of a split ring mounted in a groove on the valve stem. The use of a split ring or other removable element for the insurance member creates a problem, however, in that a hard impact of the split ring against the abutment might be sufficient to dislodge ,or removed the split ring from the groove on the valve stem. If the split ring becomes dislodged from its mounting means, it cannot perform the necessary function of limiting the maximum movement of the valve toward the cylinder.

To solve this problem, the present invention provides means for providing a peripheral wall substantially circumscribing the split ring when the latter is engaging the abutment. The-radial clearance between the peripheral wall and the split ring is sufficient to accommodate normal manufacturing and assembly tolerances but is insufficient to allow the split ring to be removed from its groove on the valve stem by radial expansion of the split ring. To best accomplish this function, the width of the opening defined by the peripheral wall should be less than the width of the valve stem adjacent the split ring groove plus two times the width of the split ring. With the several components of the valve limiting mechanism being circular in cross section, this means that the diameter of the opening defined by the peripheral wall should not exceed the diameter of the valve stem adjacent the groove plus two times the diameter of the wire which forms the split ring.

These concepts can be embodied in a valve structure which includes a body having a passage therethrough and a bore extending from the passage and a valve element including a valve head and a valve stem mounted for movement on the body to permit the valve head to open and close the passage. The valve stem projects through the bore, and the valve is biased toward a closed position by a spring which acts against a valve spring retainer carried by the valve stem. The abutment and peripheral wall can advantageously be formed in the body and define a counterbore in which the split ring or insurance member is received. The body may form a portion of the fixed structure of the internal combustion engine and may include a valve guide which contains the bore and counterbore.

Another feature of this invention which is directed to preventing engine damage and improving performance under valve float conditions involves the manner of mounting of the valve spring retainer on the valve stem. The valve spring retainer includes a bore and a counterbore through which the valve stem projects. The valve stem has a circumferential groove thereon in which a second split ring is mounted. The spring urges the valve spring retainer against the split ring therefor with the split ring being received in the counterbore of the retainer. The counterbore defines a shoulder or abutment against which the split ring bears and the peripheral wall of a counterbore is spaced radially of the split ring for the retainer so as to prevent removal thereof from its groove as a result of radial expansion. This facilitates construction in that it eliminates the multiple wedges used heretofore and positively prevents inadvertent removal of the retainer from the valve stem. To facilitate reseating of the split ring in the counterbore, the counterbore preferably widens as it extends away from the abutment.

The invention can best be understood by reference to the following description taken in connection with the accompanying illustrative drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a fragmentary sectional view of a valve for an internal combustion engine constructed in accordance with the teachings of this invention with the valve being closed.

FIG. 2 is an enlarged fragmentary sectional view with the valve open illustrating how the insurance member operates to prevent damage to the valve.

FIG. 3 is an enlarged sectional view taken generally along line 3-of FIG. 1.

FIG. 4 is an enlarged fragmentary sectional view of the valve stem, split ring and the valve spring retainer.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 illustrates a valve 11 constructed in accordance with the teachings of this invention. The valve 11 includes a body 13, a valve element 15 mounted on the body, a valve spring retainer 17 carried by the valve element and a spring 19 acting between the body and the valve spring retainer to urge the valve to the closed position shown in FIG. 1. The valve 11 is opened by a suitable cam driven actuator member 21.

The body 13 in the embodiment illustrated forms a portion of the fixed structure of an internal combustion engine. The body 13 defines a fluid flow passage 23 which opens into a combustion chamber or cylinder 25 of the engine. The body 13 defines an annular conical valve seat 27 at the mouth of the passage 23. The valve 11 may be either an intake or exhaust valve and, accordingly, the passage 23 is adapted to carry either a fuel air mixture to the cylinder 25 for combustion or to carry exhaust gases from the cylinder.

The body 13 has a bore or opening 29 coaxial with the valve seat 27 extending from the passage 23 to a location on the exterior of the body. The body 13 includes a valve guide 31 suitably rigidly mounted in the bore 29. The valve guide 31 has a cylindrical bore or opening 33 coaxial with the valve seat 27 extending therethrough. The upper end of the valve guide 31 has an annular shoulder or abutment 35 (FIG. 2) and a cylindrical peripheral wall 37 which cooperate to define a cylindrical counterbore 39 which is coaxial with the bore 33. The valve guide 31 may be formed integrally with the body 13 if desired.

The valve element includes a valve head 41 and a valve stem 43. The valve head 41 is configured so as to sealingly engage the valve seat 27 to completely block off the passage 23 from the cylinder 25. The valve stem 43 projects generally perpendicularly from the valve head 41 through the bore 33 and the counterbore 39. As best shown in FIGS. 2 and 3, the valve stem 43 has an annular circumferentially extending mounting groove 45 and a split ring 47 is mounted in the groove 45.

The valve stem 43 has an annular circumferentially extending groove 49 (FIG. 4) adjacent the upper end thereof and a split ring 51 having substantially the same configuration in plan as the split ring 47 is mounted in the groove 49. in the embodiment illustrated, each of the split rings 47 and 51 is constructed of resilient wire of circular cross section and of constant diameter. The inside diameters of the split rings 47 and 51 in relaxed condition are slightly less than the diameters of the valve stem 43 at the grooves 45 and 49, respectively, so that the split rings 47 and 51 resiliently grip their re- I spective grooves 45 and 49.

The retainer 17 has an axial bore 53 (FIGS. 1 and 4) extending therethrough and a coaxial counterbore defined by a surface 55 which is arcuate in cross section.

The surface 55 is arcuate in axial cross section and defines an axial abutment against which the split ring 51 is seated and a peripheral wall which surrounds the ring 51 to prevent radial expansion thereof. The spring 19 acts between the body 13 and the retainer 17 to urge the surface 55 against the retaining ring 51. In this fashion, the spring 19 holds the valve 11 in a closed position in which the valve head 41 tightly engages the valve seat 27 to prevent fluid flow through the passage 23.

To open the valve 1 1, the actuator member 21 which is driven by, for example, engine driven cams acts on the upper end of the valve stem 43 to urge the valve element l5 downwardly against the biasing force of the spring 19. Such downward movement of the valve element 15 separates the valve head 41 from the valve seat 27 to provide an opening between the passage 23 and the cylinder 25. Under normal operation when the valve element 15 is not floating, the actuator member 21 will not move the valve element a sufficient distance to cause contact between the split ring 47 and the shoulder 35 of the counterbore 39. Thus, under normal operating conditions the valve 11 can operate as a standard poppet valve.

if high engine speeds or other factors cause the valve element 15 to float, the valve element will move downwardly beyond the normal amount until the split ring 47 contacts the shoulder 35 are shown in FIG. 2. Further movement of the valve head 41 away from the valve seat 27 is prevented by the engagement of the split ring 47 and the shoulder 35. The location of the shoulder 35 is such that the split ring 47 will engage the shoulder 35 before the valve head 41 has travelled a sufficient distance into the cylinder 35 to cause damage.

Because the split ring 47 is radially expandable against its inherent resilience, a sharp impact against the shoulder 35 might tend to dislodge the retaining ring from its groove 45. With the present invention, the peripheral wall 37 positively prevents this because any significant radial expansion of the split ring 47 as a result of impact against the shoulder 35 is prevented by the peripheral wall 37. Thus, the peripheral wall 37 forms a radial abutment which limits radial outward movement of the split ring 47 when the latter engages the shoulder 35 to an amount insufficient to dislodge the split ring 47 from the groove 45. To positively accomplish this, the diameter of the counterbore 39 should be less than the diameter of the valve stem 43 immediately above the groove plus two times the diameter of the resilient wire which forms the split ring 47.

During normal operation of the valve 11, Le, under nonfioat conditions, the retainer 17 will be held in substantially continuous engagement with the split ring 51 by the spring 19. However, under high speed conditions the retainer 17 may axially separate from the split ring 51 to the extent that the retainer moves downwardly (as viewed in FIG. 1) beyond the split ring 51. Should this occur, the split ring 51 will remain firmly mounted on its groove 49. The retainer can be easily reseated on the split ring 51 and the curved surface assists such reseating operation and positively prevents cocking of the retainer 17 on the valve stem 43. The surface 55 circumscribes the split ring 51 radially outwardly of the split ring to thereby prevent radial expansion of the split ring to such an extent as to dislodge the split ring from the groove 49.

Relative terms such as up" and down have been I used herein merely to correspond to the orientation of the specific embodiment illustrated in the accompanying drawings and should not be considered limiting. Obviously, the concepts of the present invention are applicable regardless of the spatial orientation of the valve.

Although an exemplary embodiment of the invention has been shown and described, many changes, modifications and substitutions may be made by one having ordinary skill in the art without necessarily departing from the spirit and scope of this invention.

I claim:

1. A valve of the type usable with an internal combustion engine comprising:

a body having a fluid passage extending therethrough, said body defining a valve seat circumscribing a region of said passage, said body having an opening therein extending outwardly from said passage;

means on said body defining a bore extending therethrough;

a valve element including a valve head and a valve stem, said valve stem projecting through said bore and said valve head being adjacent said valve seat, said valve element being movable relative to said body between a closed position in which the valve head contacts the valve seat to close the passage and an open position in which the valve head is separated from the valve seat to open the passage; means on said body defining a shoulder and an inner peripheral wall defining a counterbore opening in a direction generally away from said valve seat; said valve stem having a first circumferentiallyextending groove thereon with said shoulder being intermediate said valve seat and said first groove; a radially expandable split ring in said first groove and having a portion radially outwardly of the adjacent regions of said valve stem, said split ring being cooperable with said shoulder to limit the maximum amount that said valve head can separate from said valve seat; the radial dimension of said counterbore adjacent said shoulder being less than the thickness of said valve stem radially inwardly of said split ring whereby the peripheral wall positively assures that impact of the split ring against the shoulder cannot radially expand said split ring to dislodge the split ring from said first groove;

means for biasing said valve element toward said closed position;

a valve spring retainer having a bore and a counterthe radial dimension of said counterbore of said valve spring retainer adjacent the shoulder thereof being less than the thickness of said valve stem radially inwardly of said second split ring; and each of said split rings being of substantially continuous thickness, said counterbore of said valve spring retainer having an arcuate portion which is flared outwardly as it extends axially outwardly, each of said split rings resiliently gripping the valve stem and being substantially circular in plan. 

1. A valve of the type usable with an internal combustion engine comprising: a body having a fluid passage extending therethrough, said body defining a valve seat circumscribing a region of said passage, said body having an opening therein extending outwardly from said passage; means on said body defining a bore extending therethrough; a valve element including a valve head and a valve stem, said valve stem projecting through said bore and said valve head being adjacent said valve seat, said valve element being movable relative to said body between a closed position in which the valve head contacts the valve seat to close the passage and an open position in which the valve head is separated from the valve seat to open the passage; means on said body defining a shoulder and an inner peripheral wall defining a counterbore opening in a direction generally away from said valve seat; said valve stem having a first circumferentially extending groove thereon with said shoulder being intermediate said valve seat and said first groove; a radially expandable split ring in said first groove and having a portion radially outwardly of the adjacent regions of said valve stem, said split ring being cooperable with said shoulder to limit the maximum amount that said valve head can separate from said valve seat; the radial dimension of said counterbore adjacent said shoulder being less than the thickness of said valve stem radially inwardly of said split ring whereby the peripheral wall positively assures that impact of the split ring against the shoulder cannot radially expand said split ring to dislodge the split ring from said first groove; means for biasing said valve element toward said clOsed position; a valve spring retainer having a bore and a counterbore terminating in a shoulder with the valve stem projecting through said bore, said valve stem having a second circumferentially extending groove adjacent said valve spring retainer, a second split ring in said second groove, said second split ring being received in said counterbore of said valve spring retainer, said biasing means including a spring acting between said body and said valve spring retainer; the radial dimension of said counterbore of said valve spring retainer adjacent the shoulder thereof being less than the thickness of said valve stem radially inwardly of said second split ring; and each of said split rings being of substantially continuous thickness, said counterbore of said valve spring retainer having an arcuate portion which is flared outwardly as it extends axially outwardly, each of said split rings resiliently gripping the valve stem and being substantially circular in plan. 